The Ring has so much of Sauron's malice placed in it that it instantly imposes it's own will on whoever handles it who is not the Master of the Ring. In a way the ring is self aware and seeks to be with it's Master.
If you've read The Silmarillion, Sauron was a lieutenant of an evil lord who was far more powerful than he. Sauron did learn how to create the Rings from an elf (9 for men, 7 for dwarves, helped with creating the 3 for elves and his 1 to rule), but his malice was taught by a far older power and that certainly assisted him in centralizing his power into the Ring. Plus, Sauron remembered his master coveting the Silmarils and how they did give his master some additional power, so he sought to increase his power by focalizing it in the Ring.
Because the ring only recognizes One Master, it causes all others who possess it to 'fade'. If Bilbo had possessed the Ring long enough and worn it long enough, he would have faded and become a wraith. It was both the power of the Ring that made him disappear and Bilbo not possessing any power that made him disappear when he put it on.